i agree that twa's route structure leaves a lot to be desired, but sometimes it can be a blessing for those of us MileMaxers with too much time on our hands. i took a roundtrip this past weekend from atlanta to washington,d.c. for $108 on twa. the atl-stl-iad-stl-atl trip awarded me 4,000 miles (or 8,000 with the double mile aviators promotion they are now having). then with twa's elite 50% bonus (another 2,000), it will be a total of 10,000 miles.

also, twa is pretty generous with their upgrade certificates. they only require a certificate for the non-stop distance between your departure and destination airports (atl-iad = 543 miles). one 500 mile certificate (with a 50-mile buffer) gave me first-class all the way from atl-stl-iad!! with delta, the same flights would have cost me 1,600 miles in certificates since they only use 800-mile "segment" upgrades (not valid for the least expensive fares, which is what i had purchased).

all the programs have their good and bad features. just figure out which program(s) has the features you want most, which airline seems to treat you the best, and show them your loyalty.